renderbox.h

linux下开源浏览器WebKit的源码,市面上的很多商用浏览器都是移植自WebKit

/*
 * Copyright (C) 1999 Lars Knoll ([e-mail])
 *           (C) 1999 Antti Koivisto ([e-mail])
 * Copyright (C) 2003, 2006, 2007 Apple Inc. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 *
 */

#ifndef RenderBox_h
#define RenderBox_h

#include "RenderBoxModelObject.h"
#include "ScrollTypes.h"

namespace WebCore {

enum WidthType { Width, MinWidth, MaxWidth };

class RenderBox : public RenderBoxModelObject {
public:
    RenderBox(Node*);
    virtual ~RenderBox();

    // Use this with caution! No type checking is done!
    RenderBox* firstChildBox() const;
    RenderBox* lastChildBox() const;

    int x() const { return m_frameRect.x(); }
    int y() const { return m_frameRect.y(); }
    int width() const { return m_frameRect.width(); }
    int height() const { return m_frameRect.height(); }
    
    void setX(int x) { m_frameRect.setX(x); }
    void setY(int y) { m_frameRect.setY(y); }
    void setWidth(int width) { m_frameRect.setWidth(width); }
    void setHeight(int height) { m_frameRect.setHeight(height); }
    
    IntPoint location() const { return m_frameRect.location(); }
    IntSize size() const { return m_frameRect.size(); }

    void setLocation(const IntPoint& location) { m_frameRect.setLocation(location); }
    void setLocation(int x, int y) { setLocation(IntPoint(x, y)); }
    
    void setSize(const IntSize& size) { m_frameRect.setSize(size); }
    void move(int dx, int dy) { m_frameRect.move(dx, dy); }

    IntRect frameRect() const { return m_frameRect; }
    void setFrameRect(const IntRect& rect) { m_frameRect = rect; }

    IntRect borderBoxRect() const { return IntRect(0, 0, width(), height()); }
    virtual IntRect borderBoundingBox() const { return borderBoxRect(); } 
    
    // The content area of the box (excludes padding and border).
    IntRect contentBoxRect() const { return IntRect(borderLeft() + paddingLeft(), borderTop() + paddingTop(), contentWidth(), contentHeight()); }
    // The content box in absolute coords. Ignores transforms.
    IntRect absoluteContentBox() const;
    // The content box converted to absolute coords (taking transforms into account).
    FloatQuad absoluteContentQuad() const;

    // Bounds of the outline box in absolute coords. Respects transforms
    virtual IntRect outlineBoundsForRepaint(RenderBoxModelObject* /*repaintContainer*/) const;
    virtual void addFocusRingRects(GraphicsContext*, int tx, int ty);

    // Use this with caution! No type checking is done!
    RenderBox* previousSiblingBox() const;
    RenderBox* nextSiblingBox() const;
    RenderBox* parentBox() const;

    // The height of a block when you include normal flow overflow spillage out of the bottom
    // of the block (e.g., a <div style="height:25px"> that has a 100px tall image inside
    // it would have an overflow height of borderTop() + paddingTop() + 100px.
    virtual int overflowHeight(bool /*includeInterior*/ = true) const { return height(); }
    virtual int overflowWidth(bool /*includeInterior*/ = true) const { return width(); }
    virtual void setOverflowHeight(int) { }
    virtual void setOverflowWidth(int) { }
    virtual int overflowLeft(bool /*includeInterior*/ = true) const { return 0; }
    virtual int overflowTop(bool /*includeInterior*/ = true) const { return 0; }
    virtual IntRect overflowRect(bool /*includeInterior*/ = true) const { return borderBoxRect(); }

    int contentWidth() const { return clientWidth() - paddingLeft() - paddingRight(); }
    int contentHeight() const { return clientHeight() - paddingTop() - paddingBottom(); }

    // IE extensions. Used to calculate offsetWidth/Height.  Overridden by inlines (RenderFlow)
    // to return the remaining width on a given line (and the height of a single line).
    virtual int offsetWidth() const { return width(); }
    virtual int offsetHeight() const { return height(); }

    // More IE extensions.  clientWidth and clientHeight represent the interior of an object
    // excluding border and scrollbar.  clientLeft/Top are just the borderLeftWidth and borderTopWidth.
    int clientLeft() const { return borderLeft(); }
    int clientTop() const { return borderTop(); }
    int clientWidth() const;
    int clientHeight() const;

    // scrollWidth/scrollHeight will be the same as clientWidth/clientHeight unless the
    // object has overflow:hidden/scroll/auto specified and also has overflow.
    // scrollLeft/Top return the current scroll position.  These methods are virtual so that objects like
    // textareas can scroll shadow content (but pretend that they are the objects that are
    // scrolling).
    virtual int scrollLeft() const;
    virtual int scrollTop() const;
    virtual int scrollWidth() const;
    virtual int scrollHeight() const;
    virtual void setScrollLeft(int);
    virtual void setScrollTop(int);

    virtual int marginTop() const { return m_marginTop; }
    virtual int marginBottom() const { return m_marginBottom; }
    virtual int marginLeft() const { return m_marginLeft; }
    virtual int marginRight() const { return m_marginRight; }

    // The following five functions are used to implement collapsing margins.
    // All objects know their maximal positive and negative margins.  The
    // formula for computing a collapsed margin is |maxPosMargin| - |maxNegmargin|.
    // For a non-collapsing box, such as a leaf element, this formula will simply return
    // the margin of the element.  Blocks override the maxTopMargin and maxBottomMargin
    // methods.
    virtual bool isSelfCollapsingBlock() const { return false; }
    int collapsedMarginTop() const { return maxTopMargin(true) - maxTopMargin(false); }
    int collapsedMarginBottom() const { return maxBottomMargin(true) - maxBottomMargin(false); }
    virtual int maxTopMargin(bool positive) const { return positive ? std::max(0, marginTop()) : -std::min(0, marginTop()); }
    virtual int maxBottomMargin(bool positive) const { return positive ? std::max(0, marginBottom()) : -std::min(0, marginBottom()); }

    virtual void absoluteRects(Vector<IntRect>&, int tx, int ty, bool topLevel = true);
    virtual void absoluteQuads(Vector<FloatQuad>&, bool topLevel = true);
    
    IntRect reflectionBox() const;
    int reflectionOffset() const;
    // Given a rect in the object's coordinate space, returns the corresponding rect in the reflection.
    IntRect reflectedRect(const IntRect&) const;

    virtual void layout();
    virtual void paint(PaintInfo&, int tx, int ty);
    virtual bool nodeAtPoint(const HitTestRequest&, HitTestResult&, int x, int y, int tx, int ty, HitTestAction);

    virtual void destroy();

    virtual int minPrefWidth() const;
    virtual int maxPrefWidth() const;

    int overrideSize() const;
    int overrideWidth() const;
    int overrideHeight() const;
    virtual void setOverrideSize(int);

    virtual IntSize offsetFromContainer(RenderObject*) const;
    
    int calcBorderBoxWidth(int width) const;
    int calcBorderBoxHeight(int height) const;
    int calcContentBoxWidth(int width) const;
    int calcContentBoxHeight(int height) const;

    virtual void borderFitAdjust(int& /*x*/, int& /*w*/) const { } // Shrink the box in which the border paints if border-fit is set.

    // This method is now public so that centered objects like tables that are
    // shifted right by left-aligned floats can recompute their left and
    // right margins (so that they can remain centered after being
    // shifted. -dwh
    void calcHorizontalMargins(const Length& marginLeft, const Length& marginRight, int containerWidth);

    void positionLineBox(InlineBox*);

    virtual InlineBox* createInlineBox();
    void dirtyLineBoxes(bool fullLayout);

    // For inline replaced elements, this function returns the inline box that owns us.  Enables
    // the replaced RenderObject to quickly determine what line it is contained on and to easily
    // iterate over structures on the line.
    InlineBox* inlineBoxWrapper() const { return m_inlineBoxWrapper; }
    void setInlineBoxWrapper(InlineBox* boxWrapper) { m_inlineBoxWrapper = boxWrapper; }
    void deleteLineBoxWrapper();

    virtual int lowestPosition(bool includeOverflowInterior = true, bool includeSelf = true) const;
    virtual int rightmostPosition(bool includeOverflowInterior = true, bool includeSelf = true) const;
    virtual int leftmostPosition(bool includeOverflowInterior = true, bool includeSelf = true) const;

    virtual IntRect clippedOverflowRectForRepaint(RenderBoxModelObject* repaintContainer);
    virtual void computeRectForRepaint(RenderBoxModelObject* repaintContainer, IntRect&, bool fixed = false);

    virtual void repaintDuringLayoutIfMoved(const IntRect&);

    virtual int containingBlockWidthForContent() const;

    virtual void calcWidth();
    virtual void calcHeight();

    bool stretchesToViewHeight() const
    {
        return style()->htmlHacks() && style()->height().isAuto() && !isFloatingOrPositioned() && (isRoot() || isBody());